Foam forming device



June 13, 1950 K. c. THOMPSON 2,511,420

FOAM FORMING DEVICE Filed Dec. 24, 1947 j; www@ Patented June 13, 1950 UNITED vSTATES FAQENT GFFICE FOAM FORMING DEVICE Kenneth C. Thompson, Chicago, Ill.

Application December 24, 1947, Serial No. 793,664

3 Claims. l

This invention relates Ato a foam forming device, and more kparticularly to a foam for-ming attachment for .a spray gun.

vA commonlyused type :of spray gun vcomprises a body member which vis adapted to be secured to a`hoseconnected to the pressure side of .a vacuum cleaner. A liquid container is carried by the tubular member and :is open to pressure from the vacuum cleaner hose, and the tubular member terminates in a .nozzle .portion having an opening 'for :air and liquid ,delivery .means which extend from said container. Such a spray gun is designed Afor .use inspraying .soap solutions, insecticides, etc.

While attempts have been made in the past to devise ia foam forming device adapted to be attached to such a :spray gun, such foam forming devices have A.comprised unduly complex structures involving .relatively :high material and manufacturing costs. For example, several Vsuch prior art devices have utilized a tubular member adapted to be attached to the outlet of thespray gun, said tubular member having therein a ,plurality of spaced screens through which fluid is .forced to form a foam or lather. The expense of the materials and the high manufacturing cost caused .by the requirement of mounting the screens and spacer members within the tubular member have rendered such devices impractical froma commercial standpoint. v

I have devised and am herewith disclosing and claiming an improved foam forming attachment for .a spray gun. My .novel foam forming device is adapted readily to be mounted upon and removed from a spray gun and comprises a very simply and economically manufactured device wherein a mass of `I'lbrous material is utilized to forma foam or lather. The fibrous material may be positioned in a tubular member by means of a simple manufacturing operation as compared to the complexity of mounting screens and spacers, and such brous material comprises an efcient means of producing 'a large supply of foam or lather which has many desirable uses, as for exe ample in cleaning rugs or upholstered furniture. In addition, 'my improved foam forming device is small in size and light in weight so that it may be handled with ease.

Other features and advantages of this invention will Zbe apparent from the following speciication and from the drawings in which:

Fig. l `is a vertical section through a spray gun having a foam forming device constructed in accordance with my invention mounted thereon;

Fig. 2 isa top plan View of the apparatus shown in Y1; land.

Fig. 3 is a fragmentary transverse vertical section along the line 3 3 of Fig. 1.

Referring more particularly to the drawings, the spray gun comprises a body member yI 0 which, as illustrated, has a circular transverse ,cross section and which is adapted to be secured by friction means or otherwise to the open end of a hose il which extends from a source of pressure, as from the pressure side of a lconventional domestic vacuum cleaner.

The other end of the body member Ill is turned inwardly to form a nozzle lila which terminates in an opening lb, through -which air under pressure emerges from the nozzle.

Attached to the underside of the body member B (as the parts appear in Fig. l) -is a threaded cap I2, and a container i3 lhaving a threaded top is carried by the cap i2, a gasket 12a providing a seal between the members i2 and i3. The container 'i 3 can be of any suitable material, but conventionally is formed of glass or other transparent material, and is utilized for hoiding va supply of liquid, as for example a soap solution it. An opening i5 through the body member il and the cap l2 admits air under pressure above the liquid le forcing said liquid up through a liquid de livery means comprising a small pipe l'which extends from a point near the bottom oi the icontainer i3 upwardly through the cap i2 and 'into the body member i@ Where the liquid delivery means turns at a right angle and terminates at a position coaxial with and slightly behind (speal;- ing with respect to the direction-of air flow) the air opening ib, As is well understood in the art, the flow of air through the opening Mib breaks the solid stream of liquid from the liquid delivery means into a spray.

While obviously both ends of the'liquid delivery pipe -i must be open during the operation of the spray gun, selectively operable means are provided for closing the lower end of the pipe it as desired. This means comprises a valve member ii mounted on the lower end of an L-shaped' stem i3 which extends upwardly through a guide tube l and terminates in an actuating knob 29 spaced above the top of the body member i0. A compression spring 2l surrounds a. portion of the stem i8 within the body member i@ and reacts against the bottom of the body member i0 and a stop collar 22 on the stem E8 so that the valve member il normally is seated in the lower end of the liquid delivery pipe i5 and seals said pipe. By pressing the knob 2t to overcome the resistance oi the spring 2 i, the valve member ll is moved awaf,7 from the lower end of the pipe so that liquid may pass up through said pipe,V

The foam forming device is designed to be readily attached to and removed from the spray gun above described. The foam forming device comprises a tubular member designated generally at 25, one portion a of which is of no greater, and preferably of slightly smaller, outer diameter than the outer diameter of the spray gun body member l, and another portion 25h of which is enlarged so that the inner diameter of the portion 25h is the same as the outer diameter of the spray gun body member I. In mounting the foam forming device on the spray gun the portion 25h of the tubular member 25 may be slipped over the body member i0, the tubular member 25 being secured by friction means to the body member Ill. In order to permit the member 25 to be properly mounted, said member has a slot 25e which the shaft i8 and the lower portion of the actuating knob 2El may enter, and the member 25 has an opposite larger slot 25d to bypass that portion of the body member IG Which is secured to the cover The member 25 terminates at its smaller end in an inwardly turned iiange 26 Which deiines an outlet opening 2l through which the foam or lather formed by the device may pass. A foraminous member 28, preferably of non-corrosive material (as an aluminum disk) is mounted Within the member 25 adjacent the outlet opening, and a mass of non-corrosive fibrous material 29, as for example stainless steel Wool, is packed Within the tubular member 25, the foraminous member 28 restraining said mass from entering the outlet opening 27. f desired, the foraminous member 28 may be omitted, and if a preformed cartridge of non-corrosive knit net mesh material is used, the inwardly turned iiange 26 will restrain such material from entering the outlet opening 21.

A packing member 3G which is formed of a non-corrosive material, as aluminum, and is preferably slightly tapered so that the diameter of its right-hand or rear end is slightly oversize with respect to the inner diameter of the portion 25a of the tubular member 25, is forced into the tubular member 25 behind the fibrous material 29, the member 3i! being frictionally held within the tubular member. rThe forward portion of the member 3i) which faces the nozzle Ilia is given a concave formation complementary to the formation of said nozzle so that it engages the nozzle over a substantial area adjacent the air opening Il'lb in said nozzle.

The packing member 3G has an extending portion 30d Which is of substantially the Same diameter as the air opening lilb, said extending portion preferably being slightly tapered to permit easier entry into said air opening. A iiared inlet opening 3l extends through the packing member 3l) and the extending portion 30a, and this opening is coaxial with and of larger diameter than the liquid delivery1 means, the liquid delivery pipe i6 extending into the mouth of this opening 3l. Since the opening 3l is oversized with respect to the liquid delivery means, air from the body member l@ is forced into the opening 3l along With liquid from the liquid delivery means to form a spray, and the passage of this spray through the iibrous material 29 under the spray gun pressure forms a foam or lather which emerges from the outlet opening 2'?.

ln the particular apparatus illustrated, the spray gun is of a common commercially obtainable type, and for this particular gun the tubular member 25 should have a diameter of about 31/9e inches. However, the apparatus Would be similar for use with any similar commercially obtainable type of spray guns, the face of the packing member 3 being modified to conform to the nozzle portion of any spray gun.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made Without departing from the spirit and scope of the invention as disclosed in the appended claims.

Iclaim:

1. A foam forming attachment for a spray gun having a nozzle with an opening for air and liquid delivery means coaxial with said opening, comprising: a tubular member constructed to be secured by friction means to the nozzle of said spray gun, said tubular` member having an outlet opening at one end thereof; a mass of brous material within said tubular member, said member having means adjacent said outlet opening for restraining said mass from being forced through said outlet opening; and a packing member within said tubular member, said packing member being formed to engage the outer surface of said nozzle over a substantial area adjacent the air opening in said nozzle and having an extending portion adapted to enter said air opening in said nozzle, said extending portion and packing member having an inlet opening therethrough coaxial with and of larger diameter than said liquid delivery means.

2. A foam forming attachment for a spray gun having a nozzle with an opening for air and liquid delivery means coaxial with said opening, comprising: a tubular member adapted to be secured by friction means to the nozzle of said spray gun, said member having an inwardly turned liange at one end defining an outlet opening; a mass of non-corrosive fibrous material Within said tubular member, said iiange restraining said mass from being forced through said outlet opening; and a packing member frictionally held Within said tubular member, said packing member being formed to engage said nozzle over a substantial area adjacent the air opening in said nozzle and having an extending portion adapted to enter said air opening in said nozzle, said extending portion having substantially the same outer diameter as the diameter of said air opening, and said extending portion and said packing member having an inlet opening therethrough coaxial with and of larger diameter than said liquid delivery means to provide an air space therearound.

3. A foam forming attachment for a spray gun having `a nozzle with an opening for air and a liquid delivery means coaxial with said opening, comprising: a tubular member securable to said nozzle and having an outlet opening at one end thereof; a mass of iinely-divided material within said tubular member adjacent said outlet opening; means on said tubular member for restraining said mass from being forced through said outlet opening; and a packing member rictionally held Within said tubular member, said packing member being formed to engage the outer surface of said nozzle over a substantial area adjacent the air opening in said nozzle and having an extending portion that is slightly tapered from the packing member to the inner end of said portion adapted to enter said air opening in said nozzle, said extending portion having a base diameter substantially equal to the diameter of said air opening and having an inlet, opening which extends through the packing member and the extending portion and is coaxial with and of larger diameter than said liquid delivery means.

KENNETH C. 'THOMPSON'.

REFERENCES CITED The following references are of record in the file of this partent:

Number UNITED STATES PATENTS Name Date Vellenoweth Aug. 7, 1894 Ferrell May 6, 1919 Number 

